Processes for hydrogen production and catalysts for use therein

Abstract

This invention describes a process for producing hydrogen comprising: introducing a feedstream comprising a bio-based feedstock and water into a reformer and supplying heat to the reformer; contacting the feedstream with a steam reforming catalyst disposed within the reformer to form a reformate comprising hydrogen and carbon monoxide; recovering the reformate from the reformer; contacting the reformate with steam in the presence of a water-gas shift catalyst disposed within a water-gas shift reaction zone to form a water-gas shift product stream comprising hydrogen, and the water-gas shift product stream comprises hydrogen in a greater quantity than in the reformate; heating the feedstream by heat exchange contact of the feedstream with a product stream selected from the reformate, the water-gas shift product stream or combinations thereof to transfer heat from the product stream to the feedstream prior to introducing the feedstream into the reformer.

1 . A process for producing hydrogen comprising:
 introducing a feedstream comprising a bio-based feedstock and water into a reformer and supplying heat to the reformer from a heat source to maintain the reformer at a reformer operation temperature;   contacting the feedstream with a steam reforming catalyst disposed within the reformer to form a reformate comprising hydrogen and carbon monoxide;   recovering the reformate from the reformer;   contacting the reformate with steam in the presence of a water-gas shift catalyst disposed within a water-gas shift reaction zone to form a water-gas shift product stream comprising hydrogen, wherein the water-gas shift reactor operates at a water-gas shift operation temperature that is lower than the reformer operation temperature and the water-gas shift product stream comprises hydrogen in a greater quantity than in the reformate;   heating the feedstream by heat exchange contact of the feedstream with a product stream selected from the reformate, the water-gas shift product stream or combinations thereof to transfer heat from the product stream to the feedstream prior to introducing the feedstream into the reformer.   
     
     
         2 . The process of  claim 1  wherein the bio-based feedstock comprises a material selected from the group consisting of alcohols, acids, ketones, ethers, esters, aldehydes, and combinations thereof. 
     
     
         3 . The process of  claim 1  wherein the bio-based feedstock is derived from biomass selected from the group consisting of lignin, corn, sugar cane, syrup, beet juice, molasses, cellulose, sorbitol, algae, glucose, acetates and combinations thereof. 
     
     
         4 . The process of  claim 1 , wherein the bio-based feedstock comprises ethanol. 
     
     
         5 . The process of  claim 1 , wherein the reformer is operated at a reformer operation temperature of from 500° C. to 850° C. 
     
     
         6 . The process of  claim 1 , wherein the reformate is recovered from the reformer at a recovery temperature of at least 500° C. 
     
     
         7 . The process of  claim 1 , wherein the water-gas shift reaction zone comprises a first stage and a second stage, wherein the first stage is operated at a temperature that is higher than the second stage and the feedstream is in heat exchange contact with one or more streams selected from a first stage water-gas shift product stream, a second-stage water-gas shift product stream, the reformate and combinations thereof. 
     
     
         8 . The process of  claim 1 , wherein the feedstream is introduced into the reformer as vapor at a pressure of from 150 psi to 400 psi. 
     
     
         9 . The process of  claim 1  wherein the feedstream is introduced into the reformer in the absence of compression. 
     
     
         10 . The process of  claim 1 , wherein the feedstream is introduced into the reformer at a steam to carbon molar ratio of from 2:1 to 4:1. 
     
     
         11 . The process of  claim 1 , wherein the steam reforming catalyst comprises a metal component, a modified support and a promoter. 
     
     
         12 . The process of  claim 11  wherein the metal component comprises nickel in an amount of from 0.1 wt % to 60 wt %. 
     
     
         13 . The process of  claim 11  wherein the promoter comprises a rare earth element in an amount of from 0.1 wt % to 15 wt %.